This gas on Venus could be a new sign of life

– Deep within the acid clouds above Venus,astronomers have detected something new,a gas that could be a sign of life. The gas is phosphine, a toxic moleculewith an odor of garlic and dead fish. Astronomers discovered the
compound in a cloud layerwhere temperatures are fairly closeto those on earth’s surface. Phosphine is exciting because
of where it comes from. On earth, it’s either
manufactured by humans,or it’s a natural byproduct of life. It just doesn’t show up anywhere else,and there’s no human
manufacturing on Venus. Phosphine is not sure fireproofthere are alien microbes
on the cloudy planet,but it does mean that
something is going on there. Something that we don’t understand. Here’s the backstory. Late last year, a team
at MIT put out a papercalling phosphine gas a bio signature,a substance that may come
from life on another world. The team argued that phosphine has noabiotic false positives,meaning nothing but life could
naturally produce the gason a rocky planet like earth. They suggested astronomers
look for phosphinein the atmospheres of planets
orbiting distant stars. Find phosphine and you’ve
maybe found alien life. But this year, an international team,including several researchers at MIT,started looking for phosphine
a little closer to home ,in the clouds above Venus. They used two telescopes
to break apart the lightfiltering through gases
in Venus’s atmosphere. By looking at various
wavelengths or spectra,as they pass through these molecules,scientists can find fingerprints
of the gasses present,and amazingly they found
it, a signature linein the spectrum right
where phosphine should be. It’s a pretty low concentration. One of the researchers described
it as “a few tablespoons”in an Olympic-size swimming pool. “But that’s actually quite a lotcompared to what we find on earth. And that may mean that somethingis actively replenishing the supply. To stress test their find,
the team tried to come upwith other explanations for the gas. They modeled things like
lightning strikes and meteorsto see if those events might producethis amount of phosphine. So far, nothing matches up. Now, things could change
in the months ahead. It’s possible that this
signal could be explainedby another gas, sulfur dioxide. We’ll need more observations
to confirm one gas or another. And even if it is phosphine,life may not be the best explanation. Venetian clouds are a nightmarish
place for life to survive. The clouds themselves are made
of droplets of sulfuric acid. So acidic that they’re
literally off our pH scale. Any life we’re familiar with
would face wrong odds there. And for what it’s worth,there have been other
alien false alarms before. In 1996, researchers
found what looked likefossilized bacteria in
a Martian meteorite. Then president, Bill Clinton,
even gave a speech about it. – If this discovery is confirmed,it will surely be one of
the most stunning insightsinto our universe that
science has ever uncovered. – Ultimately that claim did
not hold up to scrutiny. So the reaction among
plenty of experts right nowis curiosity, but caution. But if the evidence remains strong,it would completely
change our understandingof what makes a planet habitable. Today, we focus on planets
that look a lot like our own,but Venus may tell us we
need to expand our search. It would also raise Venus’s
clout as a place to visit. Mars has gotten a lot more attentionover the past few decades,but phosphine could inspire
new micro punting missionsto the cloudy planet. For now, this detection
is just the beginningof a long journey for astrobiologists. There are no definitive answersabout the presence of phosphine
or the way it’s created,or the question of whether or notwe’re alone in the universe. This is a big story that’s
sure to generate a lot of hype,so be wary of any “Scientists
Have Found Aliens on Venus”type headlines. Let us know in the
comments which you’ve seenand what you think of this story. And thanks for watching.